Centrifugal drier



March 4, '1930. H, C, BEHR 1,749,370

CENTRIFUGAL DRIER Filed Aug. 23,' 1928 A 4 Sheets-Sheet l l 11.? g I mjj @il il l n L@` u 45 J IZZ L j* .729 1Z0.

INVENTOR March 4, 1930; H, BEHR 1,749,370

CENTRIFUGAL DRIER Filed Aug. 23, 1928 4 Sheets-Sheet 2 INVENTOR fans f ATTORNEY March 4, 1930.

H. BEHR CENTRIFUGAL DRIER 4 Sheets-Sheet 3 Filed Aug. 23, 1928 M '44 ATTORN Y March 4, 1930. C, BEHR 1,749,370

CENTRIFUGAL DRIER Filed Aug. 23, 1928 4 Sheets-Sheet 4 Patented Mar. 4, 1930 TES- UNITED STA HANS e'BEHR, or scAnsnALE, NEW YORK l cmITImUeA-I. marian Application. led August 23,1928. Serial No. 301,478.

This'invention relates to centrifugal driers having a continuously running basket intermittently charged and discharged, a charge to be treated being admitted to the continu'- vously rotating basket jof the drier by automatic means, while the discharge of the dried solids'is also performed automatically. The drier basket receives I a measured charge from a metering chamber connected -usedfwith sugar centrifugals. To obtain as much capacity as is possible with a given ap- K paratus the metering chamber must be filled and emptied quick-ly, and this is effected in one formof my invention by filling the metering chamber by suction and by discharging it either by means ofcompressed air or by steam pressure.

A further feature of the present invention is the uniform distribution of theI mixture 'belngtreated on the circular screen ofthe f' drier,n so as to keep the system in balance.

'A\ still further feature of my invention is the utilization of-centrifugal force storedin" the treated material to a-id inA its discharge from the-machine at the p'roperI time. l In this form thev discharge isinitiated and maintained by inclined Scrapers, which are rotated relatively to the basket containing the 3'() material only during/the dischargeperiod,

but which are not eii'ectivefor discharge dur` ing the charging, purging, washing and final drying periods bybeing-then rotated in uni- 'son with the basket and material, suchvaria' tion inl rotation being caused to take place automatically. Tc effect such relative rotation, `a deviceworking somewhat after the manner of a friction clutch is employed.v

The following is a list of the illustrations to which reference will be made in these specications: A

Figure' 1 isa sectional elevation of apparatus arranged for carrying out the process of my invention with afcontinuously running separating element.A

. Fig. -2'is a plan of the lower part of the apparatus shown in Figure 1. l` Fig. `3-is an enlarged partial sectional elevation f the separating element shown with other elements in'Figs. 1 and 2.

the

\ Fig. 4 is an under side view of the upper part of the element-shown in Fig.

Fi 5 is an elevation, partly in section, o1". ischarging element shown entirely. in section in connection with other elementsy in Figure 1. A' v Fig. 6 is an end elevation of the meansfr diverting the dilute liquid to a different rer Iceptacle from that for receiving the pure with4 a larger supply-like the mixing tank liid n oo 1g. 7 1s an enlarged sectlonal elevation of the apparatus for timing and automatically controlling the 'carrying out of the various :operations of my process.

Fig. 8 is a sectional elevation ofpart of the apparatus shown in Fig. 7 taken at right an glesthereto. f Fig. 9 is a variation of the apparatus shown in Figure 1.

Referring'to the drawings lar frame of the machine, having two oppo- .site outward extending passages 2 for access to the interior and for the passage of belts driving the pulleys 3 and 4, these passages f bein vframed by the laterals 5 and the top 6. 75 The ase 7 of the frame has the central opening8 closed by the circular baseplate 9 integral with the step bearing 10 for the lower end 11 of the basket spindle 12. At 1.3 the spindle 12 is shown reduced in diameter for the pulley 3 which is held in place rotatively bythe feather 14 and against the shoulder 15 bythe nut 16. M J

Spindle 12 is shown mounted in the quill 17 and as being free to rotate therein. The upper: end of the quill 17 ismounted in the bearin 18integral with the cap plate 19, the outer ange 20 of which is secured by bolts 21 to the upper inner ian'ge 22 of the frame 1. ,Below the bearingl 18 the quill 17 is loosely 90 fitted into the sleeve 23 of the pulley 4. A screwed collar 24,l secured by set, screw 25, holds the sleeve 23 in place vertically. The` pulleys shown as 3 and 1 are driven in the same direction, but at somewhat different speeds, .by belts not shown. f

At its lower reduced end 26 the quill 17 has fitted around itthehub 27 free to slide verti- .Gally on the portion 26, but secured against i rotation'by the feather 28. The upper end of JM 1 is the circu- 70 the hub 27 is integral with the friction cone y29 adapted to engage in frictional driving Contact with the inner correspondingly coned surface of pulley 4. The lower end of the hub 27 is integral with the oppositely ta'- pered friction cone 31 and is adapted to engage the inner coned surface 32 of the pulley 3. Hub 27 has a circumferential groove33 between the friction members 29 and 31, into which is fitted loosely the collar 34 having atY opposite sides trunnions 35 which engage with suitable holes, in the double lever 36 pivoted with a pin 37 to bosses 38j-'integral with the frame 1. The other end of the lever 36 is connected by a pin 39 to the double link 40, by which it -may'be actuated tom'ove the l cone hub 27 vertically so as to engage either y the friction cone 29 with the pulley 4, or the friction cone 31 with the pulley 3. In) this way the quill 17 will be'rot-ated in unison with the shaft 12 through the pulley 3, when the vlever 36 is forced-downward, and will be ro-I tated in unison withthe pulley 4 rotating at a different rat from pulley 3 when the lever 36 is pulle upward, the opening 41 in the frame 1 lever 36.'

At its upper end the .shaft 12 is formed with a iange 43`to which is secured the conicalequalizing lbasin 44 (shown enlarged in- Fig. 3) bythe bolts 45. The Jupper edge of the basin 44.is integral with the'downwardly extending cone 46,' which in turn is made integral with the conical basket 47 through the ribs 48 and belts 49 (see Fig/4) Outwardly,- beyond the rlbs 48, the basket 47 has numerr ous groot es 50 leavingbetween them the narrow ribs 51, and connected at the-'inner and outer ends by circular grooves`52 and 53. The ribs 51 serve tdsipport the yconical screen 54, the inner edge "55 of'which is bent into the circular groove. 56and secured therein by 'the strip?. The outeredge 58 of 54 extends into the circular recess 59 in the lower face of the outer flange 60 ofthe basket 47 .e Some of the grooves 50 are .extended outwardly 'through -the flange 60 as at 61, thereby serving as outlets for the liquid driven through; v.the screen54 into the radial grooves d50 and circular groove 53'. The outer flange 60 is secured by the bolts 62 to the fiange 63 of the inwardly coned ring 64, against which the material under jtreatment Ais trifugal force.

The quill 17 at its upper end is integral with the discv 65, which at its outer edge 66 is inclined downwards so that its` upper surface .a 67 is about parallel, though not necessarily so, tothe surface of the screen 5 4, leaving a space edge 66.

68rbetween thev screen 54 and the Between the peripherylof the ledge 66 of the disc and the 'conical ,ring 64 there-isa space 69 occu ied by the inclined scraper blades 70 wlc 'are''xed to the `edge'66 but are permittingsuch movement of thev pressed by cenfreevto move over the inner!- surface of the ring 64 and that Bf the screen 54. k

The suitably inclined blades 70when rotated relatiyely to the screen 54 and the ring 64, as will be the case when the cone 29 is the screen 54 driven by pulley 3, will act to crowd the material resting against the inner surface`of the ring 64 downwardly and inwardly causing. it to escape at its lower edge 7 6 where centrifugal force drives it outwardly and against the lstationary conical ringl 77. Ring 77 diverts the discharge downwardly outside of frame 1, such dischargeA being guided to opposite sides by the inclined chutes 78. The material removed by" the blades 70 from the outer end of the space 68 under the screen 54 will be followed up and replaced by the centrifugal action of the material behind it. The slope of the screen is` such that the frictional resistance to movement of the dried material is overbalanced by the centrifugal force driviqng it outwardly.A When all of the material 1n the space 68 and on the ring 64 has been discharged, cone 29 is released from the pulley 4 and the conev 31 is engaged with the pulley 3,by the automaticmeans t be described further on, caus ing the blades O to rotate now in unison. with screen 54 and lring 64, and thus to become inactivef v Near its upper end the frame 1 is shown provided with a number of brackets 79 which supportthe base 80 ofthe' fixed cylindrical curb 81, the outer edges of these brackets fitting inside the` lugs 82 vfor the purposeof centering. Integral with the base 8O are two cylindrical walls 83 and 84. The annular ,space 85 outside these walls forms the catchment basin for the pure liquid expelled een--y trifugally from the -mi'xt'ure in the space` 68 through. the screen 54 land out through the loo passages- 50 and 61, from which it is thrown vout above. the conical deflecting ring 86 against the curb 81 and gathered in the space 85 tojbe .drawn olf through the pipe 87. The` conical ringl 86 is automatically lifted at the conclusiqn ofthe pure liquid` period of exltraction by means to be vdescribed further on,

to the position indicated by broken lines. The remaining syrup adhering to the solids and diluted with water or other liquid in a spray from the pipe 88 and now issuing` from the passages 61 is caught on the under side of the conical ring 86 and diverted downl fao 70 l driven by the pulley 4 at a slower rate than central with the axis of the machine, is

. form afseat for the conical valve 100, having an upwardly extending stem 101 guided in the hub 102 integral with tube 96 through the ribs 103. The valve 100 is held to its seat by the Aspring 104 suitably compressed against the hub 102 by jamb nuts at the upper end of the stem. i r

'Feed tube 96 is connected at its upper end through the elastic extension 106 with the outlet of the conical bottom 1084 of the charge metering chamber 109, which is rigid with the mixing tank 110 suspended from the structure above the machine.

Chamber 109 communicates with the tank 110 through (an opening 111 at some height above its bottom and outof range of the rotating stirrer arms 112. Foreign heavy material will then settle to the bottom of the tank 110 whence Iit may be 'periodically removed. Light floating coarse material is prescreen 113.1 At t vented from enteliing the chamber 109 by the e opening 111 a plate 114 lis clamped `between the inclined internal flangeof the chamber and the side of the 'tank 110 'by vsuitable bolts.v On the side adjacent l the chamber 109 the plate' 114 serves as seat :for a flap valve 118, held to its seat by a weight 119 acting on it through a lever 120 ivoted tothe fulcrum lsupport 122carried y the valve plate 114, T e valve 118 may be prevented from opening, so as to` act as a stop fvalve, by lrunning down a screwf 123 iapped into a boss on the head 125 of cham- An, opening 126 through the valved 'fitting' L 127 affords communication of chamber 109 with either apartial vacuum or a source of A `118 of the mixture-in` the tank 110, so that the.

'mixture will rapidlyI fill the'chamber 109. The vacuum, though 4not always necessary,

l ensures Vquick filling of .the chamber 109,

and is therefore specially adapted when the mixture contains a viscous liquid vand when the mixture in 110 stands at only a small height above Athe valve 118. To prevent the lmixture from Ventering-the opening 126,- the .valve 128v is raised through a rod 130 by a fioat 129 to close the opening, 126, the rod being guided above the valve 128 by a bored boss 131 ofthe fitting 127, and below the flpat 129 by a bracket 132 inl the side of the Ichamber 109. The source ofwacuum will thus be shut off, permittin the valve 118 to` be again closedby the weig 13119.

The spring whichholds theoutlet valve -100 to its seat is sfiiciently compressed to prevent the opening of the valve by the mercl weight of the mixture above it. To effect a rapid evacuation of the metering chamber anda quick filling ofthe space under the screen 54 lin the machine, steamY or com' er through the o ening 126. I v The timing of t e cycle ofalternately filling and 4discharging' the metering chamber, admitting washing fiuid .and diverting the diluted liquid to-a different destination from that for the pure liquid, forcing cone 29 into the pulley to actuate the discharging Scrapers to eject the dried solids, and then connecting said' Scrapers to the pulley through cone 31, so as to make them inoperative during the succeeding charging, purging and washing periods, islefected bythe controlling apparatus shown mounted on the girders 93.

Referring first to the scraper operating means shown on an enlarged scale by Figs.

ressed air is admitted to the metering cham- I7 and 8, this consists of the cylinder 134 fixed with'its basal fiange 135`to the endof the girders 93y by suitable bolts. A piston 137 in the cylinder 134 ispreferably formed integrlly with a rod 138 passing through the stufiing-box at the base of the cylinder. A fixed continuous pressure is'maintained in the annular spacebetween the rod 138 and the bore of the cylinder ,through a port 141 from a pipe 142. The lower end ofthe rod 138- is plvoted to the upper, ends of the links 40 operating the lever 36, as before described. It will thus be seen" that when there is only atmospheric pressure yabovethe piston 137,

the muchv hi her pressure ,effective in the J space below t e piston keeps it near the top ofi the cylinder and the cone 29 in gear with the pulley 4, thus causing a difference in rotation between the basket 47 and the Scrapers 70,'so as to effect discharge of dried solids, as before described. To depress' the piston 137 `so as to force the cone 31 into rgear with the pulley 3, causing unison of rotation of the Scrapers 70 with the basket 47, as required during the charging, purging and washing periods, pressure from the pipe 1 42 is'admitted to the space above the piston. 137 through a channel 144 in a valve 4chest 145 fsecured to the top of the cylinder 134. The

The valve chestl or chamber v145 is shown extended tothe right of the cylinder 134`in Fig 7,`containing, besides Apressure admission and outlet valves for operating the piston 137, the pressure admission and .outlet valves for controlling -the filling and diswash Water controlling valve 171. The valve 148, nearest to the cylinder 134, when lifted olf its seat 149 against the spring 150 aifords communication with atmosphere through the channel 144. Above the extended channel 144 and to the right of a valve 148 is the pressure chamber 151, supplied with vcom-- pressed air or steam from some convenient source through the pipe/system 142, 152 entering at 153. The admission valve 154 closes the port 155 by the pressure above'it and that of spring 156. When the valve 154 is lifted off its seat the pressure enters the channel v 144 and acts to depressthe piston 137, putting the-cone 31 in gear with the pulley 3 as previouslyfdescribed.

The metering chamber through thettingy 127 is in permanent communication with the channel 157 in the valve chest or chamber 145, the communicating pipe 158 being made of iiexible material to permit moderate relative displacement between the metering.

chamber and the valve chest. In the bottom of the channel 157 is fixed a small vacuum chamber 159 communicating through a lateral opening 160 and a pipe 161 with a suitable partial vacuum producing source. The

upper opening 162 of this small vacuum chamber is controlled by a valve 163 held to "its seat by the pressure of a spring 164.

When the valve 163 is lifted off its seat, vacuum is established in the channel 157 and through the communicating pipe 158 in the metering chamber 109.l so that the valve 118 is forced open and the mixture to `be treated enters to fill the metering chamber as previously described.

Between the pressure chamber 151 and the channel 157, beneath it, is a valve port 173 controlled by-the pressure admission valve 165, held to its seat by the pressure in the chamber 151 and the spring 166. 2 With the lvalve 165 lifted, pressure is admitted through the channel 157 and connection 158 by the port 126 onto the top of the mixture in the metering chamber, thereb forcing open the outlet valve 100 and rapid y discharging the chamber. The mixture charge llowing down into the rotating equalizing cone 44 has rotation 'imparted to it b frictional contact, so that 1t flows outwar ly and upwardly over the edge ofthe cone into the conical basket 47 and ultimately fills the space 68 under the screen While being rotated with the cone 44 any circumferential inequality of the outwardly flowing sheet of the moreor less fluid mixture is c'orrectedlby its tendency to assume .an 'equipotential surface under centrifugal force in a similar manner in which gravity acts to level the 'surface of liquid and semiliquid substances. f

At the extreme endof the valve chamber 145 is )a water valve chamber 167 supplied with water under moderate pressure through a pipe. 168, and communicating through a port i169 with al chamber 170 beneath, normally closed offY from the valve chamber'167r by a valve 171 under pressure of water and that of a springu 172. When the valve 171 1s lifted, Water flows through the port 169 into the chamber 170 and out through the pipe 88 into the cone 44, which imparts to 1t rotary motion and equally distributes it around the periphery in a similar way as previously described for the mixture.

The extreme end of the valve chamber 145 has a flange 174 bolted to a vertical frame 175, the lower llange'176 of which is boltedl to the double girder93. v The opening of'each of the valves 148, 154, 163, 165 and 171 is accomplished through the lifting rods 177, 178, 179, 180 and 181, actuated respectively by cams 182, 183, 184, 185 and 186, fixed on a cam shaft 187 mounted m bearings 188, 189 and rotated from some convenient source of power by such means asa pulley 190. lThe cams are'cadjusted circumferenti'ally` to Ycause lifting of each of the valves in proper succession and at the proper time intervals required for the series of functions of charging, purging, washing' and vdischarging, and such adjustment is made variable to suit conditions as by the set screws 4191 in the hubs 192 of the cams.

The"cams 182 to 186 act on the rods 177 to 181 through rollers 193, mounted in a slot of the blocks 195. The rods are adjustably screwed with their lower ends into the upper ends of the blocksand secured by Jamb nuts. The blocks 195 are guided vertically in rectangular holes in the guide bar 198, supported from the valve chamber 145 by the distance pieces 199 and bolts 200. The rod 177 has its upper end guided in a boss integral with the valve seat 149. The upper ends of the rods 17 8, 180 and 181- are guided vertically 1n the bores of the bonnets 203, 204 and 205, fitted and secured to the lower face of the valve -chamber- 145, the bonnets having .stuiiin boxes at their lower ends. `The rod 179 has its upper end guided in a stuffing box at the lower end of the vacuum chamber 159. The rollers 193 are kept'in contact with their res ective cams by springs 150, 156, 164, 166 and 1 2 by Valves.

` For the purpose of raising the conical deflector ring 86, previous to admitting wash water by the valve 171, the deflg-'ctor has fixed to itQjthe lugs208 by which it is suspended through rods 209 from the ends of levers 210, 211, 512 and 21e, the rods having Iumirqw ends pivotedf to the ends of the levers. The levers are securedwith their hubs on the ends of two parallel rock shafts 216 which are' pressing down on their respectlve v the jaw of an arm 221 opposite to and rigid with the lever 213, so that the ends of the levers 212 and 213 must rise and fall together by equal amounts in adjusting the deflector 86. The other levers 210 and 211 will also move in unison with levers 212 and 213v by the same amount, since they are rigidly connected to the same shafts 216. Movement is imparted to the system of levers 210, 211 212 and 213 by acam 222 mounted on the shaft 187 acting downwardly on a roller 223 pivoted in the jaw of an arm 225 rigid with the lever 210.

1 to engage with the fixed friction cone 302,

which is integral with'plate 19.

Starting at the point when the metering chamber 109 is empty and aboutv to receive a charge, the Aoperation of the apparatus de# scribed, and of the process carried out by its.

aid, is as follows: At this point the cam.184 is just lifting the vacuum valve 163 off its seat on the small vacuum chamber 159, which is connected to some suction source throu h the pipe 161 so that a partial vacuum will e established in the space 157 and, through the pipe connection 158, in the metering chamber 109. Such vacuum auses the supply valve '118 to be opened a d the weight 119 to be lifted by the excess 'of atmospheric pressure f acting on the supply of mixture in the tank 1 10 plus the pressure due to the height of the mixture in the tank above the opening 111.

Mixture then flows from the tank 110 into the chamber 109 'and `on reaching `the float 129 raises the lattersuiciently to force'- the valvel 128 against its seat, thereby'shuttingv offv the connection withthe suction source, Afterthis the' mixture still continues -to rise' to a polnt at which the air (or otherA gas) above 'it is sufficiently compressed to balance the' pressure in the tank 110"'ab.ove the supply opening `111. The supply'valv'e 1:18 is then .closed by the weight 119. The cam 184 in its rotation now permits the spring 164 to close the vac-y uum valve 163, and thereafter the pressure valve 165 is opened by the rotation of the cam 185, thereby permitting air or other gas under p ressure to enter the space 157 and the chamber 109. Such pressure is suicient to overf come the force of the spring 104 holdin the valve 100 to its seat, so that `thisvalve 1s eld open and ermits the metered mixture charge to be quic 1y expelled' from the chamber .109 and to flow down into-the rotating conical f equalizing basin 44.

The conical surface ofthe basin 44 by frici tional Contact imparts to the mixture its own rotation and as the mixture .is driven outwardly and upwardly by centrifugal force, 1t

is caused to assume a truly centered'surface `to th solid grains.

ofgrotation, other words, an equipotential surface aboutthe axis of rotation. And since the basin has also a truly centered surface of revolution, they mixture passing over it arrives at itsouter edge in theform of an annular zonal `stream of practically uniform thickness so that balanced distribution 0f the mixture is obtained.

From the outer edge of the basin 44 the mixture' is projectedv further out between the ribs 48 onto the inner surface of the basket 47 and beyond over the screen 54, partially piling up against the innersurface of the conical ring 64. The inner portion of the ring of mixture, constituting the complete metered icharge from the chamber 109, slopes down from a thin edge at the top according to the angle of repose of the material as indicated at 75 in Fig. 1. During and after the deposition of such charge, centrifugal force expels liquid from the mixture through the screen 54, which liquid Hows outwardly through the grooves '50 and 6l, is projected from the edge 63 against the curb 81, tlowswdown into the annular space 85 and is conveyed away z through the pipe 87. i'

In many cases it is not practicable,- or even possible, to eliminate by centrifu al force all of the pure liquid held back inetween the solid grains in themixt ure by'capillary force. 1 It then becomesnecessary to dilute the remaining, generally valuable, liquid with water or otherdiluent to enable its removal by centrifugal action and to obtain the de- .sired degree of purity of the solid part ofthe 1 mixture. Following, therefore, the period of purging of pure liquid, water is admitted into the basin 44 from the pipe 88 (Fig. l), the water admission valve 171 havino' been lifted off its seat at the proper moment y the rotation of the suitably adjusted cam 186. The water received inthe basin is given rotation through frictional contact with4 the metal of the basin and is equally distributed in itsoutward passage by centrifugal force in the same wayas described for the mixture charge, and is projected further outwardly onto and into the annularly deposited mixture charge -under the screen 54. In passing through this deposit the water dilutes and f washes away thepure liquid films sticking The dilution passes through the screen 54 and through the channels 50 and 61 and'is thrown `off at the edge 63 like the pure liquid as before described. Previousto'the admission of water .through pipe588 the deflector cone 86 has been ralsed 'to the position indicated in broken lines in Fig. 1, so that theoutward stream if diluted liquid is caught on the under side of the conev i 86 and is thereby diverted down into the annular space 90 from which it is led away through the'pipe 91. The raisinggand lowering of the cone 86 is effected at the proper times through the'system of levers 210, 211, J

,the cone 86 is again permitted to sink to its lower position through the rotation of the `cam 222. f

After a short'period suicient for the centrifugal air drying of the solids under the screen 54, these solids are ready to be discharged. During the above described operations of depositing the mixture in the basket, of expelling the pureand the diluted parts of the liquid content and of air drying the solids, the discharge blades 704 are imbedded in the charge and rotating in unison therewith and with basket 47. Such unison of rotation was secured by -the'cone 31, which was shown in the description of the apparatus to be rotatively rigid with blades 7 0, being forcec into frictional contact with the i conical bore ...of the pulley 3 rigid with `the basket 47. The required axial downward movement of the cone 31 on the sleeve 17 was caused to take place at the proper moment by the suitably adjusted rotating cam 183 which, through the rod, 178, lifted the valve 154 oli' f its seat to admit air or other iiuid under pressure on top of the piston 137, thus overbalancingthe continuously acting pressure ,jin the f annular space 140 beneath it, so as to force it down and with 'it the lever 36 pivoted to the ring 34 encircling the sleeve 27 rigid with the cone 31.l

To cause the discharge of the completely dried solids-from the basket 47 and conev64 the friction cone 31 must be withdrawn'from the"V pulley 3 andthe upper conel 29, rigid with the lcone 31 through the sleeve 27, must be raised and forced into frictional contact, with the conical'bore of the pulley 4 which is rotated at a di'l'erent,\preferably slower,

- rate than that of pulley' 3 with basket 47.

Such raising of the sleeve 27 with the cones- 31, '29 is performed by the' upward movement of the piston 137 coupled to the sleeve through/the links 40 andthe lever 36, after the pressure` admissionvalve 154 has been allowed to vbe closed by the spring`156 through the vrotationof the "cam 183, and after the compressed air above the piston and in the space 144 has been allowedto escape by the raising off its seat of the exhaust valve' 148,

accomplished by the rotation of thesuitably adjusted cam 182. The different rate of rotation from thatA of the basket 47, imparted,r

kby the pulleyj4"to the 'blades 70, causes the latter, which are suitably inclined to `the path of rotation, to scrape the ldried solids downwardly and inwardly over the inner. surface of thecone 64 and off -at its loweredge 76. `The solids'ijy'fof'f` outwardly from thisedge againstthe inner surface of the stationary cone 77, which diverts' them down outside of the frame 1 onto the inclines 78,l

which in turn divert-them to two opposite sides of the machine onto suitable gathering or conveying devices. The solids under the screen 54, inside of those being removed by rthe scraper blades 70, are drivenby the excess of the centrifugal force stored in them over their .frictional resistance to outward movement over the screen to continually follow u so as to fill up the spaces as they' are the piston and the lever and the cone 31 down, so that the latter is again in frictional coupling with the pulley 3 and the blades are again lrotating in unison with the'basket 47. The cycle of operations is thus complete and the machine ready to receive the next charge now held in the metering chamber, into which it was admitted during the time occupied by other operations of the machine. y

In the caseofFig. 9 the blades 70 and 'the cone 301 rigid therewith are only retarded v and not stopped bythe frictional engagement with the fixed cone 302,.the retardation being just suicient to eEect thefcomplete discharge of the dried solids. d

It is to be understood that the centrifugal machine shown in the drawings, while being the preferred form, is illustrative of my in-`y vention and that changes may be made within the scope of the claims without departing from the spiritofthe invention. l ,Having described lmy invention, I claim and desire to secure by Letters Patent:

1. ln acentrifugal drier forseparating liquid from solid aggregate, the combination with a conical basket so slopedthatthe materiael belng treated,.if unobstructed, would be moved outwardly over its inner surface by' dentrifugal force, there being formed on the inner surface .of the basket numerous substantially radial ribs, and passages communicating with the spaces between the ribs and passing thrjough the basket to its periphery, and means adapted to continuously rotate the basket, of a screen bedded on `the tops of the ribs, a smooth retaining cone rigid with and coned inwardly from the basket, a discharger consisting of a. disc .and blades carried upon itsperiphry and adapted to move the material being treated inwardly over the inner surface of the retaining cone, and means for selectively causing the discharger to rotate either in unison with or at a different rate of speed fromthe speed of rotation of thebasketf.,4

2. In a centrifugal drier for separating liquid from solid aggregate, the combination with a conical basket so sloped that material -being treated, if unobstructed, would be consisting vof a disc and bladescarr'ied upon its periphery and adapted to move the mater lrial being treated inwardly over the inner surface of the retaining cone, a sleeve loosely surrounding the shaft and fast with the disc, and means for selectively causing the sleeve to rotate either in unison with'or at a different rate of speed from the speed o f rotation of the sha .3. In a centrifugal drier for separating liquid from solid aggregate, the combination with a basket, a shaft carrying the basket, means for continuously rotating the shaft, a friction clutch -surface carried by the shaft, a discharging device furnished with scrapers for removing the solid material from the basket, a sleeve loosely mounted on the shaft and carrying the discharger, a second sleeve loosely surrounding the first sleeve, a friction clutch surface rigid with the second sleeve, means for rotating the second sleeve at a different rate of speed than the rotation of the shaft, a third sleeve rotatable with and axially movable on the first named sleeve, and friction clutches carried by it at its respetive. ends, `one of said clutches being adapted to couple by axialmovement 'with the first.

named clutch surface, and the other by opposite movement adapted to couple with the second named clutched surface.

4. In a centrifugal drier for separating liquid fromr solid aggregate, the combination with a basket, a shaft carrying the basket, means for continuously rotating the shaft, a friction clutch surface carried by the shaft, a discharging device furnished with scrapers for removing the solid material from the basket, a sleeve loosely mounted on the shaft and carrying the discharger, a second sleeve loosely surrounding the lirst. sleeve, a friction clutch surface rigid with the second sleeve, means for rotating the second sleeve second named clutch surface, and means for automatically shifting the'said sleeve alternately in opposite directions to couple one or the other of the friction surfaces for causing the discharging device to rotate either in unison with the'basket or at a different speed of rotation.

Signed at New York, N. Y., this 20th day of August, 1928.

` HANS C. BEHR.

at a different rate of speed than the rotation` of the shaft, a thirdsleeve rotatable with and axially movable on the first named sleeve, and friction clutches carried by it at its respective ends, one of said clutches being adapted to couple by axial movement with therst named clutch surface, and the other by ogs posite movement adapted to couple with t 

